a. Field of the Invention
This invention relates to a crash restraint system in which an inflatable is inflated to prevent a passenger in an automobile from being thrown violently against the steering wheel, dashboard or other automobile structure.
B. Description of the Prior Art
There are in the prior art various devices which cause a protective bag to inflate in front of a driver or passenger to cushion him from impact with the steering wheel, dashboard or other vehicle structure. Usually the device is activated by an inertial switch responsive to a crash impact of the automobile. This inertial switch in turn causes an inflating device to quickly inflate the collapsed bag into its inflated position deployed in front of the driver or passenger. The inflating gas is generally supplied from a source of compressed air or other compressed gas, such as shown in U.S. Pat. Nos. 3,411,808; 3,414,031 and a number of other patents in the crash restraint field.
One of the major problems in such crash restraint systems is the "out of position passenger" problem. To act as an effective cushion in a crash situation, the bag must be moved from its collapsed position to its inflated position in an extremely short period of time (in the order of 20 to 40 milliseconds). In the situation where one of the passengers (e.g. a child) happens to be leaning or standing against the dashboard when the bag inflates, or where there is a panic braking situation just prior to crash impact so that the passenger is moved against the dashboard, the rapid expansion of the bag in many prior art inflating systems will throw the passenger backwards against the car seat with such energy that the passenger may be injured. With the use of a container of high pressure gas or air, as shown in many prior art devices, even though pressure in the container declines as inflation progresses, for the pressure to be sufficiently high to inflate the bag properly during the initial stage of inflation, the pressure at the later stage of inflation still is at a level that the inflation is sufficiently rapid to possibly cause serious injury.